I built the basic cacophonator circuit over the last hour (sounds really cool), and I will work on the audio input some time tomorrow or Sunday.

One thing I noticed that may be important--I haven't read this thread in detail, but I was thinking I needed to use a 4069 for the audio input, as that seemed to be the main thing people were talking about where I was skimming. However, the circuit diagram from page 4 uses a 4049, which has a very different pinout... I would guess if you used a 4069 but connected the pins as shown in the schematic, things would not go well for the audio input. I will try both (with appropriate pin changes) and see if one does better than the other.

One other difference in mine is that I'm using a 15V bench supply rather than a 9V battery for power, but for the basic circuit that doesn't seem to make a lot of difference.

Built the audio in, heard no effect. Shifted my jack to before C13, and BARELY heard my audio--my input is a smartphone because I'm monitoring through my computer.

I believe I need some amplification of my source signal before this might work, not sure if that's relevant to anyone who was working on this before or not. I'm going to set up a little LM386 pre amp stage and see if that works any better.

Built the audio in, heard no effect. Shifted my jack to before C13, and BARELY heard my audio--my input is a smartphone because I'm monitoring through my computer.

I believe I need some amplification of my source signal before this might work, not sure if that's relevant to anyone who was working on this before or not. I'm going to set up a little LM386 pre amp stage and see if that works any better.

Amplification does get the signal through, but it doesn't sound to me like the video, it just basically mixes the audio through. No variable distortion, it's either there and competing with the oscillators, or it's not. The frequency of the oscillators/starvation of the circuit are the only things that affect how much distortion there is on the signal, not gain on the LM386, and not the pot on either the 4069 or Oscillator 4 (where it gets injected).

I'm getting suspicious about the whole project. As far as I can tell the only video of a Cacophonator that actually processes a signal is the Sascha Neudeck one. There are two other versions with inputs, neither of which actually distorts the signal (or if it does it's very subtle):
http://youtu.be/11ObmwNxL7Uhttp://youtu.be/zURxDI_QQHk
After watching Neudeck's video again I think I know what is going on. First, there are two extra knobs on his. I'm guessing he added a simple LP filter (and maybe something else) in between the audio input and the output. When he's turning the two knobs on the bottom left he's operating the added effects. The other knobs just seem to adjust the normal cacophonator squeal. When you have the noise made by the cacophonator along with and input signal that passes through a filter and maybe distortion circuit then you'd get sounds like you get in his video. It's possible that the cacophonator also passes through the filter--I can't tell. Maybe the second mystery knob adjusts the input level or else a distortion level. Here's his video:
http://www.youtube.com/watch?v=q_s4U-8V2Gg&feature=share&list=PL416C4854F84E5312
It's actually pretty brilliant. It probably doesn't work too well with guitar.

After some problems I finally build some versions with working input.
But I never kept the circuit on breadboard cause it didnt sound good enough.

The best result I ever had was to play the output of the atari punk console into Pin 14 without any amplification. It worked like one could use the cacophonator like an broken equalizer distortion resonator. really cool.

I am sure the input has to be only Pin 14 where the chip gets it voltage. Otherwise I think u would destroy the unit. If the chip doestnt get enough voltage but the inverters do ( because of the high amplificatioon) it is supposed to die!

U guyes should filter the amplified output before it goes to pin 14. Just try different capacitors against ground. This makes it sound better.

Update: the schrottophonator sold for a good 65 euros. No idea if it's a lot or not, anyway the money was welcome for the cause. And lots of people had fun playing it the whole evening._________________::U::N::S::C::H::N::E::L::L::

I finally built this puppy based on your cool antique layout, -minus-, thanks again!

One question: RV7 doesn't seem to do much of anything. Every once in a while, depending upon the positions of RV5 and RV6, maybe I notice something happening, but for the most part, nada. I've even switched out the pot to make sure it wasn't faulty.

Is this expected, or did something go wrong with my build? Everything else behaves as expected.

As far as I recall, all the pots do something. I'd need to dig it out and do some tests though.

If all other pots do something, you are close to having it working. Check the stripboard cuts on the back of the board. Make sure the components around pin 12 and pin 13 are in the right place and soldered correctly. Also, there was an issue of me posting an incorrect image of the reverse side of the board originally. Make sure there is a cut in the stripboard rail above the IC. The present image on page one is correct.

After a little poking around with a straightened paper clip, I did indeed find a cold solder joint on the pot. It looked totally fine, I've never had one of those before.

Can you describe your method of testing further? I'm not sure how that would work. Just looking for things that wiggle but shouldn't?

I used the paper clip to connect the two points on the board where the pot connects - in other words, as if the pot were dialed to 0 resistance - and immediately heard the sound change drastically. Then, by laying the paper clip across the joint between the wire and pin 1 of the pot, I heard the same change in sound, so I re-did that solder joint, and viola - the pot now works.

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